Cartridge-fuse.



A, F. DAUM.

CARTRIDGE FUSE.

APPLICATION FILED JAN.26.1912. RENEWED DEO.1,1912.

1,061,227. Patented May 6, 1913.

W I WKINVENTOR V fiaww% @@%@Mt1 WITNESSES closure or closures UNITED srarns PATENT OFFICE.

ALBERT r. DAUM', or PITTSBURGH, P NNSYLVANIA.

CARTRIDGE-FUSE.

Specification of Letters Patent.

Application filed January 28, 1912,, Serial No. 673,529. Renewed December 4, 1912. Serial No. 734,985.

To all whom it may concern:

Be known that I, ALBERT F. DnUM, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Cartridge- Fuses, of which-the following is a specifica tion.

-My invention relates to cartridge fuses and its object is to provide a novel means for clamping one or both ends of the fuse strip or wire of a cartridge fuse to the end thereof.

My improvement is especially advantageous when used with shrinkable shells or bodies, but it may be used with glass, por

celain, or other non-shrinkable bodies, with which it had the advantages hereinafter to be specified.

Referring to the accompanying drawings, Figure 1 is a side elevation of a cart-ridge fuse, shown partly in section and connected to spring-clip terminals,- Fig. 2 is a sectionshowing my improvement .used with a terminal secured to the end of the cap. Fig. 3 is a perspective of one end of the shell or body with the screw stud place, the cap and fuse strip being omitted.- Fig. 4 is an enlarged view of the left-hand end of the cartridge fuse shown on Fig. 1, the cap being screwed on the body.

Referring first to Figs; 1, 3, and 4, 1 represents the cylindrieal body or shell composed of vulcanite, porcelain, or other nonconductor of electricity. The ends of the body 1 are provided with cup-shaped caps each composed'of a cylinder'2 of good conducting material and having an end closure 3, the cylinder fittingJ preferably loosely about the end of the ody, but it may be threaded thereon, as shown in Fig. 4,01-

.one cap. The connection of the fuse strip or wire 6 with the other cap may be the same or it may be made in various known ways.

of the shell or body.

I The shown end of the strip 6 passes the head 5 in any approved way and is wound around the stem 4 close to the outer face of the head 5, which is shown to be elongated and nar row, and seated in opposite notches in the end of the bodyior shell 1 to prevent the stem from turning when the cap is screwed on or off the stem. The longitudinal corners of the head are rounded slightly as shown at 7, so as not to cut into the fuse strip 6. It is seen that, when the cap is screwed down. tightly on theste'm, it clamps the end .of the fuse strip-tightly between itself, that, is, the inclosure 3, and the outer face of the head 5; that the head and stem rigidly connected to the body 1, butv that the head and body may have slight longitudinal movement so long as the fuse strip 6 remains .intact even though the body 1 shrinks as it does when made of vulca-nite or the like;-

and that, when the fuse is melted by an Patented lllay 6, 19,13. I

cannot turn; that the head and stem' are not overload, the explosive forceaof the metallic gases may readily move the cap from its normal position so that it may by mere visualinspection be determined Whether the fuse has been blown or not.

In Fig. 1, I have shown the cylinders 2 of the caps in contactwith the well-known spring-clip terminals 8. y

. In Fig. 2, I have shown theflat bracket spring-terminal 8 secured to the end of the cap by the nut 9 on the stem 4. The dotted lines show the position taken by the cap and connected parts after the fuse has blown.

1O isa knife terminal on the cap.

As will be seen, the member 5 is free from peripheral engagement with the end cap, and is also free from any engagement with the shell 1 so far as endwise movement of the shell is concerned, the position of the member 5 within the slots of the shell simply acting to prevent the member from rotating relative to the shell, but permitting the member to bedrawn toward the endcap so as to partially lift the member from the bottom of the recesses. It will therefore be understood that I have provided a construction by means of which the clamping action. on the fuse element is provided solely by the end cap and member, and that when this clamping action is completed, the relative positions of the member and end cap are fixed,

thereby eliminating any liability of the fuse element changing its contact relationship with either part while thefuse is in service, a positive advantage where there is shrinkage of theshell, or where there is an arrangement of parts such, for instance as shown in Figs; 1 and 2 in which the end cap is free from positive connection with the shell. In the form shown in Fig. 4, the shrinkage of the fiber when it becomes dry tends to loosen the threaded connection of cap and shell so as to permit a slight play between the opposing threads, and where, as inthe construction shown in my re-issue Patent #13312, the end of the shell forms an abutment against which the memberis held to provide the clamping action on the fuse element, this play may become serious in that it tends to destroy the contact between the fuse element and the member or cap. This objection is eliminated in. the present invention by reason of the fact that the end cap and member are held in fixed relationship'so that relative movement of the shell and end cap has no effect upon the clamping action or the contact. r

In all the forms of my invention, I dispense with a separate nu'tfor clamping the fuse strip between the cap and the head of the stem, and cause the cap to perform the function of the nut, a nut being necessary only'when the terminal 8 is used.

It is clear that my invention may be applied to various connectors for electric terminals or contacts, such as switches.

I claim-- 1.. In a cartridge fuse, a cylindrical casing, a cup-shaped cap telescopic over one end of the casing, a screw-stem having a head within the cap, and a fuse strip between the head and the end-closure of the cap, the stem being threaded and the said end-closure having a vthreaded opening adapted to work on the stem.

2. In acartridge fuse, a stem, an elongated head having the longitudinalcorners next to the stem rounded, a fuse strip extending over one of the rounded corners and about the stem, and means for clamping to January, A. D. 1912.

nocnaav the said head that part'of the fuse wire which is about the stem.

3. In a re-fillable fuse, an end cap, a shell adapted to extend into said cap, a metallic member within the end cap and free from peripheral engagement with theskirt of the cap and coiiperating with. the cap 'to secure a fuse element therebetween, and means for positioning said member within the cap to provide a normally fixed relation-between said cap and member independently of the shell, said means including a stem carried by the member and-threaded to theend cap.

j 4:. In a re-fillable fuse, an end cap, a shell adapted to extendinto-said cap, a metallic member within'the end cap and free from peripheralengagement with the skirt of the cap and cooperating with the cap to secure a fuse element therebetween, and means for positioning said member within the cap to provide a normally fixed relation between said cap and member independently of the shell, said means including a stem integral with the member and threaded to the end,

cap.

5. In a refillable fuse, an end cap, a. shell adapted to extend into --said-. cap, a metallic member within the end cap and free from peripheral engagement with-the skirt of the cap and cooperating with the cap to secure a fuse element therebetwcen, and-means for positioning said memberwithin the cap to provide a normally fixed relation between 4 said cap and member independently ofthe shell, said means including a stem carried by the member and threaded to the end cap,

the shell being recessed at its end to freely receive said member, said recess preventing rotative movements ,of the member relative to the shell but permitting endwise relative movements of said parts.

Signed at Pittuburgh, Pa., this 28rd day of ALBERT F. DAUM.

Witnesses:

F. N. BA BER,

ALICE E. DUFF.

copies of this patent may be obtained for five cents each, by

addressing the Commissioner at Patents.

Washington, D. C. 

